pandora: defconfig: update

[pandora-kernel.git] / fs / splice.c

diff --git a/fs/splice.c b/fs/splice.c
index de0101a..c65b3b4 100644 (file)
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -188,6 +188,9 @@ ssize_t splice_to_pipe(struct pipe_inode_info *pipe,
        unsigned int spd_pages = spd->nr_pages;
        int ret, do_wakeup, page_nr;
 
+       if (!spd_pages)
+               return 0;
+
        ret = 0;
        do_wakeup = 0;
        page_nr = 0;
@@ -211,6 +214,7 @@ ssize_t splice_to_pipe(struct pipe_inode_info *pipe,
                        buf->len = spd->partial[page_nr].len;
                        buf->private = spd->partial[page_nr].private;
                        buf->ops = spd->ops;
+                       buf->flags = 0;
                        if (spd->flags & SPLICE_F_GIFT)
                                buf->flags |= PIPE_BUF_FLAG_GIFT;
 
@@ -554,6 +558,24 @@ static const struct pipe_buf_operations default_pipe_buf_ops = {
        .get = generic_pipe_buf_get,
 };
 
+static int generic_pipe_buf_nosteal(struct pipe_inode_info *pipe,
+                                   struct pipe_buffer *buf)
+{
+       return 1;
+}
+
+/* Pipe buffer operations for a socket and similar. */
+const struct pipe_buf_operations nosteal_pipe_buf_ops = {
+       .can_merge = 0,
+       .map = generic_pipe_buf_map,
+       .unmap = generic_pipe_buf_unmap,
+       .confirm = generic_pipe_buf_confirm,
+       .release = generic_pipe_buf_release,
+       .steal = generic_pipe_buf_nosteal,
+       .get = generic_pipe_buf_get,
+};
+EXPORT_SYMBOL(nosteal_pipe_buf_ops);
+
 static ssize_t kernel_readv(struct file *file, const struct iovec *vec,
                            unsigned long vlen, loff_t offset)
 {
@@ -854,6 +876,13 @@ EXPORT_SYMBOL(splice_from_pipe_feed);
  */
 int splice_from_pipe_next(struct pipe_inode_info *pipe, struct splice_desc *sd)
 {
+       /*
+        * Check for signal early to make process killable when there are
+        * always buffers available
+        */
+       if (signal_pending(current))
+               return -ERESTARTSYS;
+
        while (!pipe->nrbufs) {
                if (!pipe->writers)
                        return 0;
@@ -932,6 +961,7 @@ ssize_t __splice_from_pipe(struct pipe_inode_info *pipe, struct splice_desc *sd,
 
        splice_from_pipe_begin(sd);
        do {
+               cond_resched();
                ret = splice_from_pipe_next(pipe, sd);
                if (ret > 0)
                        ret = splice_from_pipe_feed(pipe, sd, actor);
@@ -995,13 +1025,17 @@ generic_file_splice_write(struct pipe_inode_info *pipe, struct file *out,
        struct address_space *mapping = out->f_mapping;
        struct inode *inode = mapping->host;
        struct splice_desc sd = {
-               .total_len = len,
                .flags = flags,
-               .pos = *ppos,
                .u.file = out,
        };
        ssize_t ret;
 
+       ret = generic_write_checks(out, ppos, &len, S_ISBLK(inode->i_mode));
+       if (ret)
+               return ret;
+       sd.total_len = len;
+       sd.pos = *ppos;
+
        pipe_lock(pipe);
 
        splice_from_pipe_begin(&sd);
@@ -1167,7 +1201,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
        long ret, bytes;
        umode_t i_mode;
        size_t len;
-       int i, flags;
+       int i, flags, more;
 
        /*
         * We require the input being a regular file, as we don't want to
@@ -1210,6 +1244,7 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
         * Don't block on output, we have to drain the direct pipe.
         */
        sd->flags &= ~SPLICE_F_NONBLOCK;
+       more = sd->flags & SPLICE_F_MORE;
 
        while (len) {
                size_t read_len;
@@ -1222,6 +1257,15 @@ ssize_t splice_direct_to_actor(struct file *in, struct splice_desc *sd,
                read_len = ret;
                sd->total_len = read_len;
 
+               /*
+                * If more data is pending, set SPLICE_F_MORE
+                * If this is the last data and SPLICE_F_MORE was not set
+                * initially, clears it.
+                */
+               if (read_len < len)
+                       sd->flags |= SPLICE_F_MORE;
+               else if (!more)
+                       sd->flags &= ~SPLICE_F_MORE;
                /*
                 * NOTE: nonblocking mode only applies to the input. We
                 * must not do the output in nonblocking mode as then we